The “News & Views†post about poisoned neighborhood dogs from the August 15 Brentwood News caught my attention. These dogs were likely poisoned by a common potent anticoagulant rodenticide, which causes death by internal bleeding within about 72 hours. During that time, the rodent’s movements become sluggish, and it easily falls prey to house cats, dogs, and wild predators.
While some poisoned animals can survive with a 6-week course of vitamin K, many succumb to the poison, with blood running from their eyes and nostrils. California’s Department of Fish & Game cites studies in which 92% of raptors collected in San Diego County, 82 mountain lions tested since 2005, and 79% of endangered San Joaquin kit foxes in the Bakersfield area showed anticoagulant rodenticide in their blood.
According to Wildcare, a Marin County wildlife rehabilitation center, in 2012 alone, 84% of their patients tested showed a positive result! The EPA is starting the process to ban the most deadly of these rodenticides from the consumer (not professional) market.
Homeowners, building managers and professional rodent control companies are using these rodenticides rather than relying on traps and exclusion tactics (patching holes and cracks). But there’s an alternative: night-flying rodent control — Barn Owls, beautiful white birds of prey that are quite adapted to life near humans. A family of five Barn Owls can consume 3,000 rodents in one breeding season.
Barn Owls, found in virtually all habitats, from rural to urban, are about 14†length with a wingspan of 42†and soft plumage that muffles the sound of their feathers, ensuring a silent approach to prey which their acute hearing targets in total darkness. The birds are believed to mate for life.
A pair can incubate two broods of 2-18 eggs during the nesting season. They prefer warm climates with mild winters. Nearby open grassland (a park for example) is essential for hunting. They will often nest quite close to homes in backyards or parks. In addition to being beautiful, Barn Owls are incredibly effective hunters. With their high metabolism they can consume their body weight (roughly 18 oz. — 1 to 6 rodents per night). Pound for pound, Barn Owls consume more rodents than possibly any other creature.
In conjunction with Wildcare, the Hungry Owl Project (HOP) has successfully installed owl boxes in vineyards and suburban neighborhoods in Marin, Sonoma and Napa counties. The boxes provide otherwise absent living quarters for owls, which must nest in holes, tree cavities, the fronds of palm trees (which provide camouflage), and in one case in the light fixture of a Sears store!
You can’t move an owl to an area and expect it to stay – you must provide a suitable nest. Barn Owls are not territorial and can easily be attracted to an area with the right nest box. There are many premade owl boxes and kits available for purchase (see www.allaboutbirds.org/BarnOwl; www.barnowlboxes.com), and they are easy to build. Wildcare’s plywood owl boxes are made by high school and middle school students and local Scout troops.
Because they are nocturnal birds, Barn Owls rarely bother pets. Their young beg during the five-week period when they are being fed; however, most owl hosts say the trade-off is worth it. To rid an area of rodents, especially in an urban setting, trapping and exclusion tactics are also necessary. Nevertheless, if you read the preceding text, you will know that rodenticides should never be used when employing owls for rodent control.
Observing nesting barn owls can be a rewarding experience. And with it comes the comfort of being able to walk your dog without worrying about its eating a poisoned rodent.